In recent years, there have been cases where X-ray computed tomography (CT) devices capture a subject that is placed on a bed or an operating table of a different medical-image diagnostic apparatus. In such a case, an X-ray CT apparatus is moved on a rail so that it is moved to a position where it is possible to capture a subject that is placed on a bed or an operating table.
To discharge heat within a gantry in the above-described X-ray CT apparatus, for example, air is drawn from the side of a rail of the gantry, it is flowed to the ceiling surface of the gantry by a fan that is provided in an upper section of the gantry, and air is discharged out of the gantry from the ceiling surface of the gantry.